Inflatable safety device for motor vehicle

ABSTRACT

A safety device for a motor vehicle adapted to protect a vehicle occupant from injury in the event of a collision of a motor vehicle. The safety device includes a pressurized gas supply unit comprising pressurized gas generating means and sealing means in closing engagement with a discharge spout of the pressurized gas generating means. The sealing means includes a first split cap member releasably attached to the discharge spout to hermetically seal off the same engaging the discharge spout, a second cap member associated with the first cap member for hermetically seal off the discharge spout, and explosive means for releasing, when activated, the first and second cap members from the discharge spout thereby to provide communication between the discharge spout and the inflatable confinement whereby the pressurized gas is admitted into the inflatable confinement to actuate the same to its protective position.

Usui et al.

[ 1 Marni I974 [54] INFLATABLE SAFETY DEVICE FOR MOTOR VEHICLE [75]Inventors: Keizaburo Usui, Yokosuka; Michio Yamaguclii, Yokohama;Yasuhiro Saito, Tokyo; 'llsugio Noda, Kawagoe; Takaslii Mitani, Kawagoe;Shinzo Tsuji, Kawagoe; Kenichi Mitsuhashi, Tokyo, all of Japan [73]Assignee: NissanMotor Company Limited,

Yokohama City, Japan 22 Filed: Apr. 21, 1971 211 Appl. Nb; 136,051

[52] US. Cl. 280/150 AB, 137/68 5 1 1 11 1 c1. B60r 21/08 [58 newot'Seai-ch ..280/150 AB; 137/67, 68; 222/3; 220/89 A, 47

[56] Reierences Cited UNITED STATES PATENTS 3 1971 Ekstrom ..280/150 AB2/1948 McDowell H1960 Heckethorn et al. 280/89 A X PrimaryExaminer-Kenneth H. Betts Attorney, Agent, or Firm--William E. OBrien;George A. Depaoli; Donal E. McCarthy 57 ABSTRACT A safety device for amotor vehicle adapted to protect a vehicle occupant from injury in theevent of a collision of a motor vehicle. The safety device includes apressurized gas supply unit comprising pressurized gas generating meansand sealing means in closing engagement with a discharge spout of thepressurized gas generating means. The sealing means includes a firstsplit cap member releasably attached to the discharge spout tohermetically seal off the same engaging the discharge spout, a secondcap member associated with the first cap member for hermetically sealoff the discharge spout, and explosive means for releasing, whenactivatQ the first and second cap members from the discharge spoutthereby to provide communication between the discharge spout and theinflatable confinement whereby the pressurized gas is admitted into theinflatable confinement to actuate the same to its protective position.

5 Claims, 5 Drawing Figures INFLATABLE SAFETY DEVICE FOR MOTOR VEHICLEThis invention relates to a safety device for a motor vehicle and, moreparticularly, to a safety device for protecting a vehicle occupant frominjury during a collision of the vehicle with an obstruction.

A known safety device used in a motor vehicle usually includes aninflatableconfinement or protector bag which is normally held in acollapsed or folded position. The confinement is located between thevehicle occupant and structural parts of the vehicle such as awindshield, an instrument panel and a steering wheel whereby, when theconfinement is inflated as a result of an impact or collision of themotor vehicle, the vehicle occupant is prevented from contacting thestructural parts of the vehicle.

In order that the safety device operates reliably, it is desired thatthe inflatable confinement be expanded and projected to its protectiveposition as fast as possible when a collision is encountered by themotor vehicle. Improvements have heretofore been made on the safetydevice for instantaneously detecting an impact encountered by the motorvehicle and for causing the inflatable confinement to assume theprotective position as rapidly as possible.

The inflatable confinement is actuated to its expanded position with apressurized gas which is supplied from an appropriate pressurized gassupply unit. This unit includes a normally closed pressurized gasgenerator adapted to produce the pressurized gas when opened and asuitable sealing means normally closing the pressurized gas generator.The sealing means is associated with an impact-responsive triggeringmeans which is actuated in response to the collision of the motorvehicle. The sealing means is released from the pressurized gasgenerator when the triggering means is actuated, allowing thepressurized gas into the collapsed inflatable confinement. Thisinvention is thus directed generally to the thus arranged pressurizedgas supply unit and more particularly to the sealing means of thisparticular unit.

It is, therefore, an object of this invention to provide a safety devicehaving an improved pressurized gas supply unit by which the pressurizedgas is supplied to the inflatable confinement immediately when thetriggering means is actuated during a collision ofa motor vehicle.

Another object of this invention is to provide a safety device having animproved gas supply unit which is simple in construction and whichoffers ease of assembling during production.

In general. these and other objects and features of this invention maybe attained in a pressurized gas supply unit which includes apressurized gas generator having a pressurized gas discharge spoutthrough which communication is established with the infaltableconfinement when the gas generator is opened, and a rupturable sealingmeans releasably in closing engagement with the discharge spout of thepressurized gas generator. In one embodiment of this invention, therupturable sealing means includes a unitary cap member which isreleasably attached to the pressurized gas discharge spout of thepressurized gas generator through which the sealing means is in closingengagement with the discharge spout of the pressurized gas generator,and a split cap member which is integral with the unitary cap member andwhich engages with the discharge spout of the pressurized gas generator.The unitary cap member has formed therein at least one weakened portionwhich is loaded with an explosive rneansfor rupturing the unitary capmember into pieces when activated in response to an impact resultingfrom a collision of the motor vehicle and consequently providingcommunication between the discharge spout of the pressurized gasgenerator and the inflatable confinement. The pressurized gas is thusallowed into the collapsed inflatable confinement, which is consequentlyexpanded to its protective position. In another embodiment, therupturable sealing means includes'an inner split cap member engagingwith the discharge spout of the pressurized gas generator, and an outercap member which is releasably attached to the inner split cap member.The outer split cap member is provided with an explosive means at asubstantially central portion thereof for releasing the outer cap memberfrom the inner split cap member thereby to release the inner cap memberfrom the discharge spout of the pressurized gas generator uponactivation of the explosive means so that the communication between thedischarge spout of the pressurized gas generator and the inflatableconfinement is established.

In the accompanying drawings:

FIG. 1 is a schematic view showing a general construction of the safetydevice which is dealt with by this invention;

FIG. 2 is a sectional view of a pressurized gas supply unit according tothis invention for use in the safety device of FIG. 1;

FIG. 3 is a top plan view of a sealing means forming part of thepressurized gas supply unit shown in FIG. 2;

FIG. 4 is a view similar to FIG. 2 but shows a modification of thepressurized gas supply unit shown therein; and

FIG. 5 is a section on line V-V of FIG. 4.

Referring first to FIG. ll, there is schematically shown a generalconstruction of the safety device in which th improvement proposed bythis invention is to be incorporated. The safety device largelycomprises an impact responsive triggering means It) which is adapted tobe actuated in response to an impact resulting from the collision of themotor vehicle. The triggering means it) is associated with or connectedto a pressurized gas supply unit Ill which is adapted to supply apressurized gas when the triggering means 10 is actuated. Thepressurized gas supply unit It includes a pressurized gas generatorwhich may be constructed and arranged in any desired manner. Thepressurized gas generator may, for instance, contain a gas underpressure or a liquefied gas which is ready for conversion into a gasunder pressure. Or otherwise, the pressurized gas generator may containan explosive which is adapted to produce a gas under pressure whenactivated or blown up by suitable means. The pressurized gas supply unitIII is connected to an inflatable confinement or a protector bag 12which may be secured to any desired part or parts of the motor vehicle.The inflatable confinement 112 is normally stowed in a contracted orfolded position and, when the pressurized gas supplied from .thepressurized gas supply unit ii is admitted thereto,

the inflatable confinement is expanded and projected to a positionintervening between the vehicle occupant and the structural parts of thevehicle cabin, as previously noted.

According to this invention, the pressurized gas supply unit 11 shown inFIG. 1 is improved with a view to rapidly allowing the pressurized gasinto the inflatable confinement 12 when the impact is encountered by themotor vehicle. A preferred form of the pressurized gas supply unitconstructed to this end is illustrated in FIG.

Referring now to FIG. 2, the pressurized gas supply unit largelycomprises a pressurized gas generator 13 and a rupturable sealing means14. The gas generator 13, partially shown in section, is constructed andarranged in any desired manner as previously discussed and produces thepressurized gas when opened. The gas generator 13 is provided with apressurized gas discharge spout 13a which is normally closed by therupturable sealing means 14 and which is permitted to communicate withthe inflatable confinement 12 (FIG. 1) when opened. The rupturablesealing means 14 is thus releasably in closing engagement with thecircumferential end of the discharge spout 13a. The sealing means 14includes a sealing member 15 which is releasably attached to thedischarge spout 13a, a unitary cap member 16 which retains the sealingmember 15 to hermetically seal off the discharge spout 13a, and a splitcap member 17 which is integral with the unitary cap member 16. Thesplit cap member 17 is shown to comprise substantially identical halves17a and 17b having semicircular cross sections and engaging with theperipheral wall of the discharge spout 13a. The split cap member 17 isformed between the identical halves 17a and 17b with slots 17c and 17d.As seen in FIGS. 2 and 3, the unitary cap member 16 is formed in a sideportion 16a thereof with weakened or yielding portions 18 and 19 whichare in line with each other and which are in alignment with the slots17c and 17d of the split cap member 17, respectively. The weakenedportions 18 and 19 are shown as consisting of grooves 18a and 18b andgrooves 19a and 19b, respectively. The unitary cap member 16 is formedin an end portion 16b thereof with a hole 16c. The hole 16c of theunitary cap member 16 and the slots 17c and 17d of the split cap member17 constitute further yielding portions in cooperation with the yieldingportions 18 and 19 of the unitary cap member 16. The unitary cap member16 has bottomed holes 20 and 21 formed in the weakened portions 18 and19, respectively. The bottomed holes 20 and 21 receive therein explosivemeans 22 and 23, respectively, which are associated with and activatedby the impact-responsive triggering means 10 which is previouslymentioned. Thus, the unitary cap member 16 and the split cap member 17comprise two parts 14a and 14b connected with each other along theweakened portions 18 and 19 and 17c and 17d. The explosive means 22 and23 may include suitable explosive charge which is fired when theimpact-responsive triggering means 10 is actuated.

In the event of a collision of the motor vehicle with an obstruction,the impact-responsive triggering means 10 responds to the impactresulting from the collision. The triggering means 10 is actuated tofire the explosive means 22 and 23 so that the explosive charges areactivated. This causes the unitary cap member 17 to be ruptured alongthe weakened portions 18 and 19 to separate the two parts 14a and 14b ofthe unitary and split cap members 16 and 17 from each other along theyielding portions, i.e., the weakened portions 18 and 19, the hole 160and the slots 17c and 17d so that the sealing member 15 isinstantaneously released from the discharge spout 13a of the pressurizedgas generator 13 to cause the discharge spout 13a to communicate withthe inflatable confinement 12 (FIG. 1). The pressurized gas is thenadmitted into the inflatable confinement 12 through the discharge spout13a. The inflatable confinement 12 which has been in the contractedposition is consequently expanded and projected to the protectedposition, preventing the vehicle occupant from contacting the structuralparts of the motor vehicle.

FIG. 4 illustrates a modified form of the pressurized gas supply unitfor use in the safety device according to this invention. This modifiedpressurized gas supply unit is substantially similar to that shown inFIGS. 2 and 3 and, therefore, like parts and elements are designated bythe same numerals with primes added to them.

In this modified form of the pressurized gas supply unit, the rupturablesealing means 14 includes, in addition to the sealing member 15', aninner split cap member 25 engaging with the discharge spout l3'a of thepressurized gas generator 13 to retain the sealing member 15 and anouter cap member 26 which is releasably attached to the inner split capmember 25 along yielding portions, that is, a border 260 between anexternal end portion of the inner split cap member 25 and an internalend portion of the outer cap member 26 and a border 26h between anexternal side portion of the inner split cap member 25 and an internalside portion of the outer cap member 26. The sealing member 15' isprovided with a packing 27 to prevent the flow of the pressurized gasbetween the discharge spout 13a and the peripheral wall portion of thesealing member 15' engaging therewith. As seen in FIG. 5, the innersplit cap member 25 is shown as consisting of three substantiallyidentical portions 25a, 25b and 25c but may consist of more or lessidentical portions, if desired. The inner split cap member 25 has abridge portion 28 formed at a substantially central portion thereofwhich is adapted to abut against the outer surface of the sealing member15 thereby to prevent the sealing member 15 from being released from thedischarge spout 13a.

It is to be noted in this instance that although the split cap member 17in the arrangement of FIGS. 2 and 3 is shown as integral with theunitary cap member 16, the inner split cap member 25 is independent fromthe outer cap member 26. The outer cap member 26 is adapted tofrictionally engage with the outer peripheral wall or the external sideportion of the inner split cap member 25 through a pin 29 to maintainengagement between the discharge spout 13a and the inner split capmember 25 so that the sealing means 14' is prevented from being releasedfrom the discharge spout 13a of the pressurized gas generator 13' duringa normal travelling condition of the motor vehicle. It should beunderstood that the outer cap member 26 may be releasably attached tothe inner split cap member 25 by an appropriate adhesive or any othersuitable fastening means instead of the pin 29. As shown in FIG. 4, theouter cap member 26 is formed with a projection 30 which extendsoutwardly from the end portion of the outer cap member 26. Theprojection 30 has formed therein a hole 31 into which an explosive means32 is disposed. The explosive means 32 includes an explosive cartridge33 having therein a suitable explosive charge which is fired when theimpact-responsive triggering means (FIG. 1) is actuated. Designated at34 is a packing which prevents the fluid flow passing through the hole31. A support 35 is attached to the end of the projection 30 to supportthe explosive means 32, securely in the hole 3].

ln the event of a collision of the motor vehicle, the explosive means 32is activated upon actuation of the triggering means 10, so that theouter cap member 26 is released from the inner split cap member 25 alongthe yielding portions, i.e., the borders 26a and 2612 between the innerand outer cap members 25 and 26 due to a reaction applied thereto. Thiscauses thhe inner split cap member 25 to be released from the dischargespout 13'a of the pressurized gas generator 13' and the sealing member15' is instantaneously released from the discharge spout 13a by means ofthe pressurized gas in the pressurized gas generator 13' to providecommunication between the disdharge spout l3a and the inflatableconfinement 12. The pressurized gas is then admitted into the inflatableconfinement 12, which is consequently expanded to its protectiveposition.

It will now be understood from the foregoing description that thepressurized gas supply unit embodying this invention is advantageousbecause the pressurized gas is allowed into the inflatable confinementalmost instantaneously when the impact is encountered by the motorvehicle and because the pressurized gas supply unit is simple inconstruction and economical to manufacture. The pressurized gas supplyunit according to this invention is thus not only reliable inperformance but adapted for quantity production especially on account ofthe ease assembling the component parts.

What is claimed is:

l. A pressurized gas supply unit according to claim 17, wherein said capmeans comprises:

A. a first split cap member, divided into at least two parts andengaging with said discharge spout of said pressurized gas generatingmeans for retaining said releasable sealing means to hermetically sealoff said discharge spout, and

B. a second cap member, engaging said first split cap member at aninternal end portion and an internal side portion of said second capmember, respectively, with an external end portion and an external sideportion, respectively, of said first split cap member, said second capmember frictionally engaging at said internal side portion thereof withsaid external side portion of said first split cap member, therebymaintaining engagement between said discharge spout of said pressurizedgas generating means and said first split cap member, said yieldingportion of said end portion of said cap means comprising a borderbetween said external end portion of said first split cap member andsaid internal end portion of said second cap member, each of saidyielding portions of said side portion of said cap means comprising aborder between said external side portion of said first split cap memberand said internal side portion of said second cap member, said explosivemeans being mounted in said second cap member, said second cap memberbeing released from said first split cap member along said yieldingportions due to a reaction acting on said second cap member upondetonation of said explosive means thereby causing release of said firstsplit cap member from said discharge spout.

2. A pressurized gas supply unit according to claim 1, wherein saidsecond cap member has a projection extending outwardly from an externalend portion of said second cap member, said explosive means beingmounted in said projection to release said second cap member from saidfirst split cap member when activated.

3. in a safety device for protecting a vehicle occupant from injury bysudden impact imposed on a motor vehicle and having an inflatableelement having a deflated position and an inflated protective position,a pressurized gas supply unit comprising pressurized gas generatingmeans storing a source of a pressurized gas for inflating saidinflatable element and having a pressurized gas discharge spoutcommunicating with said inflatable element, releasable sealing means inclosing engagement with said discharge spout of said pressurized gasgenerating means, cap means engaging with said discharge spout of saidpressurized gas generating means for retaining said releasable sealingmeans to hermetically seal off said discharge spout, said cap meanshaving an end portion having at least one yielding portion and a sideportion having at least two yielding portions which cooperate with saidyielding portion of said end portion, said cap means comprising at leasttwo parts connected with each other along at least two of said yieldingportions, and explosive means mounted relative to said yielding portionin said cap means for separating said at least two parts of said capmeans from each other along said yielding portions to release said capmeans and accordingly said releasable sealing means from said dischargespout of said pressurized gas generating means when said explosive meansis detonated in response to a sudden impact, thereby providingcommunication between said discharge spout and said inflatable elementso that pressurized gas is admitted into said inflatable element toinflate same to its protective position.

4. A pressurized gas supply unit according to claim 3, wherein said capmeans comprises at least two parts connected with each other along saidyielding portions of said side portion, said explosive means is disposedin said cap means near each of said yielding portions of said sideportion to divide said cap means into said at least two parts along saidyielding portions of said side portion, thereby separating said at leasttwo parts from each other along said yielding portions upon detonationof said explosive means.

5. A pressurized gas supply unit according to claim 4, wherein saidyielding portion of said end portion of said cap means comprises a holeand each of said yielding portions of said side portion of said capmeans comprises a weakened portion located adjacent said explosive meansand a slot which is in alignment with said weakened portion.

1. A pressurized gas supply unit according to claim 17, wherein said capmeans comprises: A. a first split cap member, divided into at least twoparts and engaging with said discharge spout of said pressurized gasgenerating means for retaining said releasable sealing means tohermetically seal off said discharge spout, and B. a second cap member,engaging said first split cap member at an internal end portion and aninternal side portion of said second cap member, respectively, with anexternal end portion and an external side portion, respectively, of saidfirst split cap member, said second cap member frictionally engaging atsaid internal side portion thereof with said external side portion ofsaid first split cap member, thereby maintaining engagement between saiddischarge spout of said pressurized gas generating means and said firstsplit cap member, said yielding portion of said end portion of said capmeans comprising a border between said external end portion of saidfirst split cap member and said internal end portion of said second capmember, each of said yielding portions of said side portion of said capmeans comprising a border between said external side portion of saidfirst split cap member and said internal side portion of said second capmember, said explosive means being mounted in said second cap member,said second cap member being released from said first split cap memberalong said yielding portions due to a reaction acting on said second capmember upon detonation of said explosive means thereby causing releaseof said first split cap member from said discharge spout.
 2. Apressurized gas supply unit according to claim 1, wherein said secondcap member has a projection extending outwardly from an external endportion of said second cap member, said explosive means being mounted insaid projection to release said second cap member from said first splitcap member when activated.
 3. In a safety device for protecting avehicle occupant from injury by sudden impact imposed on a motor vehicleand having an inflatable element having a deflated position and aninflated protective position, a pressurized gas supply unit comprisingpressurized gas generating means storing a source of a pressurized gasfor inflating said inflatable element and having a pressurized gasdischarge spout communiCating with said inflatable element, releasablesealing means in closing engagement with said discharge spout of saidpressurized gas generating means, cap means engaging with said dischargespout of said pressurized gas generating means for retaining saidreleasable sealing means to hermetically seal off said discharge spout,said cap means having an end portion having at least one yieldingportion and a side portion having at least two yielding portions whichcooperate with said yielding portion of said end portion, said cap meanscomprising at least two parts connected with each other along at leasttwo of said yielding portions, and explosive means mounted relative tosaid yielding portion in said cap means for separating said at least twoparts of said cap means from each other along said yielding portions torelease said cap means and accordingly said releasable sealing meansfrom said discharge spout of said pressurized gas generating means whensaid explosive means is detonated in response to a sudden impact,thereby providing communication between said discharge spout and saidinflatable element so that pressurized gas is admitted into saidinflatable element to inflate same to its protective position.
 4. Apressurized gas supply unit according to claim 3, wherein said cap meanscomprises at least two parts connected with each other along saidyielding portions of said side portion, said explosive means is disposedin said cap means near each of said yielding portions of said sideportion to divide said cap means into said at least two parts along saidyielding portions of said side portion, thereby separating said at leasttwo parts from each other along said yielding portions upon detonationof said explosive means.
 5. A pressurized gas supply unit according toclaim 4, wherein said yielding portion of said end portion of said capmeans comprises a hole and each of said yielding portions of said sideportion of said cap means comprises a weakened portion located adjacentsaid explosive means and a slot which is in alignment with said weakenedportion.